freesabaiCron expression explainer
Paste a cron expression (crontab) and read it in plain words, such as "At 09:30, on Monday through Friday", with the next runs in the time zone you choose. It checks the format and tells you which field is wrong. It works for standard 5-field cron. It runs in your browser.
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minute (0-59) · hour (0-23) · day of month (1-31) · month (1-12 or JAN-DEC) · day of week (0-7 or SUN-SAT, 0 and 7 are Sunday)
| Field | Written | Matches |
|---|
Times are shown in the chosen time zone. A time that does not exist when daylight saving starts is skipped. If both the day of the month and the day of the week are given, a run happens when either matches (as in Vixie cron).
How to use it
- Paste a cron expression in the box, or press an example below. The explanation and the next runs appear at once.
- Choose the time zone your server uses (your device's zone is the default) and how many runs to see.
- Read the table of what each field matches. If a field is wrong you are told which one and why.
Frequently asked questions
In what order are the 5 fields of a cron expression?
Minute, hour, day of month, month, day of week. For example 30 9 * * 1-5 is 09:30 on Monday to Friday. * means every value, , makes a list, - a range and / a step: */15 means every 15.
What if both the day of the month and the day of the week are given?
Standard (Vixie) cron runs when the day of the month matches or the day of the week matches. For example 0 0 13 * 5 runs on every 13th and on every Friday, not only on Friday the 13th. This tool calculates it that way.
Can I use a cron with 6 fields (with seconds)?
Not on this page. Standard Linux cron has 5 fields. Quartz (Java) and some other systems have 6 or 7 fields with seconds or a year, and special characters such as L and #, which differ from the standard form. This page tells you when it finds more than 5 fields.
Good to know
- Most servers run cron in the server's time zone, which is often UTC, not Thai time. If a job must run at 09:00 Thai time (UTC+7) on a UTC server, write 02:00.
- Month names (JAN) and day names (MON) are not case sensitive, and 7 and 0 are both Sunday.
- The tool looks up to 8 years ahead. If the date asked for does not exist (like 30 February) it says there is no run.
Your data stays on your device
Everything runs in your browser. What you type, paste or open is not sent to freesabai's servers or anyone else's, and is not kept in the browser: close the page and it is gone. The site only counts how many times this page was opened and how many times someone copied or saved a result (never what was pasted or the result, and you can switch the counting off in the footer; see the privacy policy).
Report a problem or suggest an idea
Found a bug, or want this tool to do more? Tell us on the feedback page. No sign-up.
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